In that respect, it is indeed crazy.
But from a wider perspective, his record is actually very patchy, meaning that after (occasional) early successes, he's still been sacked from almost every job he's ever had, making you wonder how he keeps getting appointed in the first place.
Maybe his relationship with "Super Agent" Jorge Mendes helps? Apparently Nuno was his very first client when he moved into football and the pair have remained close ever since, so that Nuno can put forward an impressive list of Mendes players he can sign when being interviewed for jobs?